Mcahufacture of hydroxy compounds of aromatic hydrocarbons



LOUIS M. DENNIS, OF T'IHACA, NEW YORK.

MANUFACTURE OF HYDRO X Y COMPOUNDS 0F AROMATIC HYDROCONS.

incense.

No Drawing.

ful Improvement in the Manufacture of Hydroxy Compounds of Aromatic Hydrocarbons, of which the following is a specification.

My invention relates to a process of treating aromatic hydrocarbons wherein the hydrocarbon is sulfonated to form a sulfonic acid of that hydrocarbon, the sulfonic acid separated from the excess of sulfuric acid and neutralized with a suitable base or salt, the resulting sulfonate fused with an alkali hydroxid to form a salt of the hydroxy compound of the hydrocarbon, the hydroxy compound set free by treatment of an aqueous solution of this salt with CO .the hydroxy compound being then separated from the solutionand the residual carbonate liquor treated so as to separate and recover from it substantially pure alkali carbonate, which carbonate may be used to neutralize the sulfonic acid obtained as above.

Up to the present time, so far as I am aware, with the exception of the processes disclosed by me in my U. S. Letters Patent" No. 1,211,923, dated January 9, 1917 and No. 1,212,612, dated January 16, 1917, no process 'has been placed in successful commercial operation whereby sulfonic acid has been separated from the excess of sulfuric acid and obtained substantially free therefrom. I make use of my disclosures in said patents referred to in this present process.

Furthermore in processes of this character where CO has been used to set free the hydroxy compound, the resulting carbonate liquor has contained alkali sulfates and sulfites. If now this carbonate liquor beused to neutralize a sulfonic acid or a mixture of a sulfonic acid and sulfuric acid, the product contains in addition to the salt of the sulfonic acid appreciable quantities of the sulfate, which latter is prejudicial to the subsequent successful working of the process.

. Moreover, the sulfite present in the carbonate liquor will be. decomposed on neu Specification of Letters Patent.

Patented Nov. 4, 1919.

Application filed February 6, 1917. Serial No. 146,903.

tralization and thus 10st,. unless the S0 gas is recovered by some suitable process.

My newprocess obviates the disadvantages and losses caused by the presence of appreciable amounts of sulfates and sulfites in'theneutralizing liquor.

I shall describe my process in-connection with the formation of phenol from benzene mono-sulfonic acid although the process "is as well applicable to the formation of other hydroxy compounds, such as are derivable from benzene di-sulfonic acids and napthalene sulfonic acids.

Benzene is s'ulfonated with sulfuric acid, preferably with fuming sulfuric acid, and the resulting mixture of benzene sulfonic acid and sulfuric acid treated with a solvent which will dissolve the sulfonic acid but not the sulfuric acid and the sulfonic acid ex- The sulfonic acid is then neutralized bya suitable salt or base, preferably sodium carbonate substantially free from sulfates or sulfites, and obtained in the manner described below, or by sodium hydroxid obtained from such sodium carbonate. The sodium benzene sulfonate thus formed is fused with solid sodium hydroxid to form sodium phenolate; Sodium sulfite and sodium sulfate are also formed in this fusion. The product of the fusion, consisting of sodium phenolate, sulfate and sulfite, is then dissolved in water and CO passed through the solution. This results in the liberation of phenol, which is separated from the solution by suitable mean s, and there remains carbonate liquor containin sodium carbon-- ate, sodium bicarbonate, so dium sulfate and S0 lost.

bonate substantially free from sodium sulfate and sodium sulfite, will separate out in solid form.

I do not restrict my invention to its use in connection with any particular aromatic hydrocarbon or to the formation of any particular hydroxy compound thereof, further thanv the scope of the appended claims demands.

I claim:

1. A process of treating aromatic hydrocarbons consisting in sulfonating the hydrocarbon with sulfuric acid in excess, freeing the sulfonic acid from the residual sulfuric acid, then neutralizing the separated sulfonic acid, fusing the sulfonate thus produced with an alkali metal hydroxid to form a salt of a hydroxy compound of-the hydrocarbon with formation of the sulfate and sulfite of the alkali metal of the alkali metal hydroxid, treating an aqueous solution of theproducts of the fusion with CO to form a hydroxycompound of the hydrocarbon with formation of the carbonates of the alkali metal of the alkali metal hydroxid, freeing the hydrbxy compound from the solutionand separating out the alkali carbonates substantially free from sulfate and sulfite. i

2. A process of treating aromatic hydrocarbons consisting in sulfonating the hydrocarbon with sulfuric acid in excess, freeing the sulfonic acid from the residual sulfuric acid, then neutralizi the separated sulfonic acid with an a ali metal carbonate, fusing the sulfonate' thus produced with an alkali metal hydroxid to form a salt of a hydroxy compound of the hydrocarbon with formation of the sulfate and sulfite of. the alkali metal of the alkali metal hydroxid, treating an aqueous solution of the products of the fusion with CO to form a hydroxy compound of the hydrocarbon with formation of the carbonates of the alkali metal of the alkali metal hydroxid, freeing the hydroxy compound fromthe solution and Separating 'out the alkalicarbonates substantially free from sulfate andsulfite. 3. A process of treating aromatic hydrocarbons consisting in sulfonating the hydrocarbon with sulfuric acid in excess, freeing the sulfonic acid' from the residual su1 furic acid, then neutralizing the separated Sl1lfonic acid with sodium carbonate, fusing the sulfonate thus produced with sodium hydroxid to form a sodium salt of a hydroxy compound of the hydrocarbon with formation of sodium sulfate and sodium sulfite, treating an aqueous solution of the products of the fusion witlrCO to forma hydroxy compound of the hydrocarbon with formation of sodium carbonate and sodium bicarbonate, freeing the hydroxy compound from the solution and separating out .,the

, carbonate, fusing the dried sodium sulfonate thus produced with caustic soda, passing CO containing gases into an aqueous solution of the fused material whereby sodium carbonate is formed, separatin the sodium carbonate from the liquor and employing the separated sodium carbonate substantia 1y free from other compounds to ne gralize another portion of the sulfonic acl 5. A process of treating benzene consisting in sulfonating the benzene with sulfuric acid in excess, freeing the benzene sulfonic acid from the residual sulfuric acid, then neutralizing the separated sulfonic 'acid, fusing the sulfonate thus produced with an alkali metal hydroxid to form a phenolate with formation of the sulfate and sulfite of the alkali metal of the alkali metal hydroxid, treating an aqueous solution of the products of the fusion with CO, to form phenol with formation of the carbonates of the alkali metal of the alkali, metal hydroxid, freeing the phenol from-the solution and separating out the alkali carbonates-"substantially fi'ee from sulfate and sulfite 6. A process of treating benzene consisting in sulfonating the benzene with fuming sulfuric acid, freeing the benzene sulfonic acid from the residual sulfuricacid, then neutralizing the separated sulfonic acid with sodium carbonate, fusing the sulfonate thus produced with sodium hydroxid to form sodium phenolate with formation of sodium sulfate and sodium sulfite, treating an aqueous solution of the products of the fusion with CO to form phenol with formation of sodium carbonate and sodium bicarbonate, freeing the phenol ffrom the ,solution and separating out the carbonates substantially free fromsulfate and sulfite.

7. A- process of treat benzene which comprises sulfonatin the benzene with sulfuric acid in excess, freeing the sulfonic acid from the residual sulfuric acid, then neucarbonate from the liquor and employing tralizing the separated sulfonic acid with the separated sodium carbonate substah- 10 alkali comprising sodium carbonate, fusing tially free from other compounds to neutralthe dried sodium benzene sulfonate thus ize another portion of the sulfonic acid. produced with caustic soda, passing CO In testimony whereof I have signed this containing gases into an aqueous solution specification.

of the fused material whereby sodium carbonate is formed, separating the sodium LOUIS M. DENNIS. 

